POS1020 BIOLOGICAL DMARD TREATMENT IN PSORIATIC ARTHRITIS IS LIKEWISE EFFECTIVE IN PATIENTS WITH HIGH AND WITH LOW JOINT COUNTS – RESULTS FROM THE SWISS CLINICAL QUALITY MANAGEMENT (SCQM) FOR RHEUMATIC DISEASES COHORT STUDY
Authors: B. Moeller, A. Ciurea, R. Micheroli, M. J. Nissen, E. Papagiannoulis, A. Scherer, G. Scholz, N. Yawalkar
Journal: Annals of the Rheumatic Diseases (2022)

Background Biological and targeted synthetic (b/tsDMARDs) may be used in absent remission in psoriatic arthritis (PsA) independent of a defined number of affected joints. However, minimum three swollen and three tender joints are a common inclusion criterion in trials of b/tsDMARDs, and less is currently known about their effectiveness in PsA patients with low joint counts. Objectives To characterize PsA patients with low or high joint counts (LJC/HJC), analyze their drug treatment in routine care, and estimate the effectiveness of a first bDMARD in LJC and HJC patients. Methods We defined patients with less than three tender or swollen joints as LJC, and those with at least three tender and swollen joints as HJC patients. Patients were twice categorized according to their joint counts at registration in the registry, and at start of a first bDMARD (Table 1). We compared HJC and LJC at registration for current and future DMARD therapies, and at start of a first bDMARD for treatment effectiveness, using drug retention in univariate and in multivariable Cox regression models. Table 1. Selected characteristics of bDMARD naïve PsA patients with a low and with a high number of affected joints at start of their first bDMARD. Variable Levels HJC % high LJC % low N all p bDMARD type TNFi 176 92.6 175 88.8 351 =0.22 OMA 14 7.4 22 11.2 36 csDMARD cotherapy yes 117 61.6 90 45.7 207 &lt;0.01 csDMARD history naive 23 12.1 55 27.9 78 &lt;0.01 tsDMARD_history naive 175 92.1 177 89.8 352 =0.47 Dactylitis history yes 115 60.5 60 30.5 175 &lt;0.01 HLA B27 yes 12 11.5 28 23.3 40 =0.02 MDA Yes 0 0.0 17 8.6 17 &lt;0.01 DAPSA remission 0 0.0 12 6.1 12 &lt;0.01 Dactylitis Yes 93 49.0 33 16.8 126 &lt;0.01 Enthesitis Yes 63 61.8 55 47.0 118 =0.03 BMI mean (SD) 27.65 (5.05) 26.58 (4.72) 333 =0.046 MASES mean (SD) 2.86 (3.93) 1.61 (2.47) 219 =0.005 HAQ-DI mean (SD) 0.77 (0.58) 0.60 (0.50) 292 =0.010 EQ-5d mean (SD) 62.22 (20.63) 67.22 (16.27) 294 =0.022 Patient global mean (SD) 5.93 (2.41) 4.83 (2.58) 288 &lt;0.001 Tender joint count mean (SD) 10.15 (8.93) 4.92 (8.17) 387 &lt;0.001 Swollen joint count mean (SD) 7.16 (4.91) 1.37 (2.15) 387 &lt;0.001 Patient pain mean (SD) 5.96 (2.47) 4.85 (2.51) 290 &lt;0.001 Abbreviations: DAPSA: Disease activity of PsA. BMI: Body mass index, EQ-5d: European Quality of Life Measurement in five dimensions. HAQ-DI. Health assessment questionnaire disability index. HJC: High joint count, LJC: Low joint count, MASES: Maastricht ankylosing spondylitis enthesitis score, MDA: minimal disease activity, OMA: other mode of action than TNFi. Results We followed DMARD therapies for median (IQR) 3.2 (1.6, 5.0) in 675 LJC patients and for 3.4 (1.8, 5.2) years in 334 HJC patients. LJC patients at registration as well as at start of a first bDMARD were less often female, with less severe skin, enthesitis, dactylitis and nail involvement. Furthermore, LJC patients had lower disability indices and a more favorable health related quality of life. When defined at registration, LJC were as frequent as HJC patients on csDMARDs, but less often on bDMARDs. During their follow-up, a csDMARD, a first and a second bDMARD were less often and on average later commenced in LJC than in HJC patients. However, when defined at start of a first bDMARD, drug retention did not significantly differ between LJC and HJC patients (Figure 1). Figure 1. Multivariable adjusted Cox regression model for discontinuation of a first bDMARD. Abbreviation: JC_group_base: Low and high joint count groups at baseline. Conclusion The majority of Swiss PsA patients is in LJC status, which also means a better status in most PsA domains than in HJC patients. LJC status was associated with established bDMARD therapy and with slower treatment escalation. However, bDMARDs were likewise effective in bDMARD-naïve LJC and HJC patients, and should not withhold only for reasons of a low joint count. References [1]Gossec et al. 2020, Annals of the Rheumatic Diseases 79 (6): S700–712. [2]Gladman et al. 2021, The Journal of Rheumatology 48 (12): 1824–29. Acknowledgements I acknowledge all patients, physicians and researchers of the Swiss Clinical Quality Management (SCQM) for rheumatic diseases Program, and Celgene for funding of this research. Disclosure of Interests Burkhard Moeller Speakers bureau: Novartis, MSD, Synergy, Eli Lilly, Bristol-Myers-Squibb, Janssen-Cilag, AbbVie and Pfizer, Grant/research support from: Celgene, Amgen, Vifor, Adrian Ciurea Speakers bureau: Abbvie and Novartis, Raphael Micheroli: None declared, Michael J. Nissen Speakers bureau: Abbvie, Celgene, Eli-Lilly, Janssen, Novartis and Pfizer, Eleftherios Papagiannoulis: None declared, Almut Scherer: None declared, Godehard Scholz: None declared, Nikhil Yawalkar Speakers bureau: Abbvie, Amgen, Celgene, Janssen, Lilly, Novartis, Pfizer